Obesity is a major health issue in the United States and in many nations throughout the world. Obesity leads to increased risk of premature death and increased risk of comorbid conditions such as type II diabetes, hypertension, and heart disease. Approximately, one-third of U.S. adults are obese, i.e., have a body-mass index (BMS) greater than 30.
Current treatments for obesity include diet, exercise, drugs, and surgery. Non-surgical treatments have shown little effectiveness, and surgery is typically indicated only for those individuals who are morbidly obese, i.e., for those who have a BMS of greater than 40 or for those individuals who have a BMS of greater than 35 with a comorbid condition. Surgical interventions include restrictive interventions which limit food intake, malabsorptive interventions which limit nutrient absorption, and combinations thereof, i.e., interventions which both limit food intake and limit nutrient absorption. One of the most effective surgical procedures is the Roux-en-Y gastric bypass, which is a combination surgery to create a small stomach pouch (to limit food intake) and to bypass sections of the intestine responsible for absorption. Roux-en-Y gastric bypass, however, is normally irreversible.
In the normal workings of the gastrointestinal system, food travels from the mouth and then through the esophagus to the stomach. In the stomach, gastric juice is secreted and mixes with the food to produce chyme, i.e., partially digested food. The chyme then empties into the small intestine through the pylorus, i.e., the region of the stomach which connects to the duodenum. In the small intestine, chyme mixes with digestive fluids. In particular, in the duodenum (i.e., the upper portion of the small intestine which is proximate to the stomach), chyme mixes with bile and pancreatic fluid.
As a result of the mixing of chyme with digestive fluids including pancreatic fluid and bile in the small intestine and, more particularly, in the duodenum, chyme is chemically broken down so that nutrients contained therein may be absorbed across the wall of the small intestine. Specifically, carbohydrates are broken down into simple sugars, proteins are broken down into amino acids, and fats are broken down into fatty acids. Pancreatic fluid and, more particularly, the digestive enzymes contained therein, aid(s) in the digestion of proteins, carbohydrates, and fats, while bile aids in the emulsification, digestion, and absorption of fats. Reabsorption of the products of digestion and, more particularly, reabsorption of fatty acids and simple sugars in the duodenum, however, can ultimately lead to the deposition of fat deposits in the body and, consequently, weight gain.
In view of the foregoing, methods which modify the normal workings of the gastrointestinal system to minimize digestion of food in the stomach and to minimize the digestion of fats and carbohydrates and the reabsorption of the products of digestion (particularly, fatty acids and simple sugars) in the duodenum would be useful for treating individuals who are overweight and, more particularly, individuals who are obese.
The need exists for low cost, less invasive interventions for the treatment of obesity, including morbid obesity.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.